About the Captive Broodstock Program

Russian River Coho Salmon Captive Broodstock Program

Salmon all along the west coast have faced tremendous adversity for many years. Coho salmon in California are currently estimated to be no more than 15% of their 1940s abundance. Since the gold rush, salmon populations have been steadily declining due to a number of factors, including stream diversion, damming, mining, timber harvesting, agricultural runoff, and overfishing, in addition to natural predation, drought, and climate change. Salmon numbers have gotten so low that California and Oregon had to completely shut down the 2008 and 2009 commercial salmon fishing seasons for Chinook. Coho salmon have had a particularly difficult time, to the point that the Central California Evolutionarily Significant Unit is now on the State and Federal Endangered Species Lists. In Central California, the only remaining viable wild population is in Lagunitas Creek in western Marin County and, even there, the annual return is but a small fraction of historic runs. A little farther north, in the Russian River watershed that spans Sonoma and Mendocino counties, the return has been so small that restoration efforts have expanded to include the artificial stocking of juvenile coho salmon from wild, local genetic stocks.

The Russian River Coho Salmon Captive Broodstock Program is working to supplement the wild Russian River coho population in the hope of restoring it to a sustainable size. Since 2001, a collaborative partnership including the US Army Corps of Engineers, the National Oceanic and Atmospheric Administration Fisheries Service, the California Department of Fish and Game, the Sonoma County Water Agency, and the University of California Cooperative Extension/ California SeaGrant Extension Program, have been breeding coho salmon from local genetic stock at Warm Springs Hatchery and releasing them as juveniles into historic coho streams in the Russian River watershed.

Ben White (USACE) releasing young-of-the-year coho into Sheephouse Creek.

UC Cooperative Extension and Sea Grant's role in the Coho Program is to monitor wild and program coho salmon in the stream environment to evaluate the efficacy of the program, and to work with program partners to apply advances in scientific knowledge to its management. Monitoring activities include downstream migrant smolt trapping in the spring, snorkel surveys in the summer, and spawner surveys in the winter. Biologists also use innovative PIT-tag technology to track program fish with Passively-Integrated Transponder tags at all life stages through the use of channel-spanning antennas and handheld transceivers. 

PIT-tag antennas help Sea Grant biologists track rearing juveniles, outmigrating smolts, and returning adult coho.

To learn more about the program and the efforts of different program partners to help this imperiled species, please read past editions of our newsletter, the Coho Monitor.

Coho Monitor July 2005
Coho Monitor August 2006
Coho Monitor February 2010